package com.xuecheng.media.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.j256.simplemagic.ContentInfo;
import com.j256.simplemagic.ContentInfoUtil;
import com.xuecheng.base.exception.XueChengPlusException;
import com.xuecheng.base.model.PageParams;
import com.xuecheng.base.model.PageResult;
import com.xuecheng.base.model.RestResponse;
import com.xuecheng.media.mapper.MediaFilesMapper;
import com.xuecheng.media.mapper.MediaProcessMapper;
import com.xuecheng.media.model.dto.QueryMediaParamsDto;
import com.xuecheng.media.model.dto.UploadFileParamsDto;
import com.xuecheng.media.model.dto.UploadFileResultDto;
import com.xuecheng.media.model.po.MediaFiles;
import com.xuecheng.media.model.po.MediaProcess;
import com.xuecheng.media.service.MediaFileService;
import io.minio.*;
import io.minio.messages.DeleteError;
import io.minio.messages.DeleteObject;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.compress.utils.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.io.*;
import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.util.Date;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

/**
 * @author Mr.M
 * @version 1.0
 * @description
 * @date 2022/9/10 8:58
 */
@Service
@Slf4j
public class MediaFileServiceImpl implements MediaFileService {

    @Autowired
    MediaFilesMapper mediaFilesMapper;

    @Autowired
    MinioClient minioClient;

    @Autowired
    MediaFileService mediaFileService;

    @Autowired
    MediaProcessMapper mediaProcessMapper;

    // 存储普通文件
    @Value("${minio.bucket.files}")
    private String bucket_mediafiles;

    // 存储视频文件
    @Value("${minio.bucket.videofiles}")
    private String bucket_video;

    @Override
    public MediaFiles getFileById(String mediaId) {
        return mediaFilesMapper.selectById(mediaId);
    }

    @Override
    public PageResult<MediaFiles> queryMediaFiels(Long companyId, PageParams pageParams, QueryMediaParamsDto queryMediaParamsDto) {

        //构建查询条件对象
        LambdaQueryWrapper<MediaFiles> queryWrapper = new LambdaQueryWrapper<>();

        //分页对象
        Page<MediaFiles> page = new Page<>(pageParams.getPageNo(), pageParams.getPageSize());
        // 查询数据内容获得结果
        Page<MediaFiles> pageResult = mediaFilesMapper.selectPage(page, queryWrapper);
        // 获取数据列表
        List<MediaFiles> list = pageResult.getRecords();
        // 获取数据总数
        long total = pageResult.getTotal();
        // 构建结果集
        PageResult<MediaFiles> mediaListResult = new PageResult<>(list, total, pageParams.getPageNo(), pageParams.getPageSize());
        return mediaListResult;

    }

    @Override
    public UploadFileResultDto uploadFile(Long companyId, UploadFileParamsDto uploadFileParamsDto, String localFilePath,String objectName) {

        // 文件名
        String filename = uploadFileParamsDto.getFilename();
        // 先得到扩展名
        String extension = filename.substring(filename.lastIndexOf("."));

        // 得到mimeType
        String mimeType = getMimeType(extension);

        String defaultFolderPath = getDefaultFolderPath();
        // 文件的md5值
        String fileMd5 = getFileMd5(new File(localFilePath));
        if(StringUtils.isEmpty(objectName)){
            // 使用默认年月日去存储
            objectName = defaultFolderPath + fileMd5 + extension;
        }

        boolean result = addMediaFilesToMinIO(localFilePath, mimeType, bucket_mediafiles, objectName);
        if (!result) {
            XueChengPlusException.cast("上传文件失败");
        }
        // 将文件信息保存到数据库
        MediaFiles mediaFiles = mediaFileService.addMediaFilesToDb(companyId, fileMd5, uploadFileParamsDto, bucket_mediafiles, objectName);
        if (mediaFiles == null) {
            XueChengPlusException.cast("文件上传后保存信息失败");
        }
        // 准备返回的对象
        UploadFileResultDto uploadFileResultDto = new UploadFileResultDto();
        BeanUtils.copyProperties(mediaFiles, uploadFileResultDto);

        return uploadFileResultDto;
    }

    /**
     * @param companyId           机构id
     * @param fileMd5             文件md5值
     * @param uploadFileParamsDto 上传文件的信息
     * @param bucket              桶
     * @param objectName          对象名称
     * @return com.xuecheng.media.model.po.MediaFiles
     * @description 将文件信息添加到文件表
     * @author Mr.M
     * @date 2022/10/12 21:22
     */
    @Transactional
    public MediaFiles addMediaFilesToDb(Long companyId, String fileMd5, UploadFileParamsDto uploadFileParamsDto, String bucket, String objectName) {
        //从数据库查询文件
        MediaFiles mediaFiles = mediaFilesMapper.selectById(fileMd5);
        if (mediaFiles == null) {
            mediaFiles = new MediaFiles();
            //拷贝基本信息
            BeanUtils.copyProperties(uploadFileParamsDto, mediaFiles);
            mediaFiles.setId(fileMd5);
            mediaFiles.setFileId(fileMd5);
            mediaFiles.setCompanyId(companyId);
            mediaFiles.setUrl("/" + bucket + "/" + objectName);
            mediaFiles.setBucket(bucket);
            mediaFiles.setFilePath(objectName);
            mediaFiles.setCreateDate(LocalDateTime.now());
            mediaFiles.setAuditStatus("002003");
            mediaFiles.setStatus("1");
            //保存文件信息到文件表
            int insert = mediaFilesMapper.insert(mediaFiles);
            if (insert < 0) {
                log.error("保存文件信息到数据库失败,{}", mediaFiles.toString());
                XueChengPlusException.cast("保存文件信息失败");
            }
            log.info("保存文件信息到数据库成功,{}", mediaFiles.toString());
        }
        // 记录待处理任务
        addWaitingTask(mediaFiles);

        return mediaFiles;

    }

    /**
     * 添加待处理任务
     * @param mediaFiles
     */
    private void addWaitingTask(MediaFiles mediaFiles){
        // 获取文件的mimeType
        // 文件名称
        String filename = mediaFiles.getFilename();
        // 文件扩展名
        String extension = filename.substring(filename.lastIndexOf("."));
        String mimeType = getMimeType(extension);
        if (mimeType.equals("video/x-msvideo")){ // 如果是avi视频写入待处理任务
            MediaProcess mediaProcess = new MediaProcess();
            BeanUtils.copyProperties(mediaFiles,mediaProcess);
            // 状态是未处理
            mediaProcess.setStatus("1");
            mediaProcess.setCreateDate(LocalDateTime.now());
            mediaProcess.setFailCount(0); // 失败次数默认0
            mediaProcess.setUrl(null);
            // 向MediaProcess插入记录
            mediaProcessMapper.insert(mediaProcess);
        }

    }

    @Override
    public RestResponse<Boolean> checkFile(String fileMd5) {
        // 先查询数据库
        MediaFiles mediaFiles = mediaFilesMapper.selectById(fileMd5);

        if (mediaFiles != null) {
            // 桶
            String bucket = mediaFiles.getBucket();
            // objectname
            String filePath = mediaFiles.getFilePath();

            // 如果数据库存在再查询 minio
            GetObjectArgs getObjectArgs = GetObjectArgs.builder()
                    .bucket(bucket)
                    .object(filePath)
                    .build();
            try {
                FilterInputStream inputStream = minioClient.getObject(getObjectArgs);
                if (inputStream != null) {
                    inputStream.close();
                    // 文件已存在
                    return RestResponse.success(true);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        // 文件不存在
        return RestResponse.success(false);
    }

    @Override
    public RestResponse<Boolean> checkChunk(String fileMd5, int chunkIndex) {

        // 根据md5得到分块文件的路径
        String chunkFileFolderPath = getChunkFileFolderPath(fileMd5);

        // 如果数据库存在再查询 minio
        GetObjectArgs getObjectArgs = GetObjectArgs.builder()
                .bucket(bucket_video)
                .object(chunkFileFolderPath + chunkIndex)
                .build();
        try {
            FilterInputStream inputStream = minioClient.getObject(getObjectArgs);
            if (inputStream != null) {
                inputStream.close();
                // 文件已存在
                return RestResponse.success(true);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return RestResponse.success(false);
    }

    @Override
    public RestResponse<Boolean> uploadChunk(String fileMd5, int chunk, String localChunkFilePath) {
        // 分块文件的路径
        String chunkFilePath = getChunkFileFolderPath(fileMd5) + chunk;
        // 获取
        String mimeType = getMimeType(null);
        // 将分块文件上传到minio
        boolean b = addMediaFilesToMinIO(localChunkFilePath, mimeType, bucket_video, chunkFilePath);
        if (!b) {
            return RestResponse.validfail(false, "上传分块文件失败");
        }
        return RestResponse.success(true);
    }

    @Override
    public RestResponse<Boolean> mergechunks(Long companyId, String fileMd5, int chunkTotal, UploadFileParamsDto uploadFileParamsDto) {
        // 分块文件所在目录
        String chunkFileFolderPath = getChunkFileFolderPath(fileMd5);
        // 找到分块文件调用minio的sdk进行文件合并
        List<ComposeSource> sourceList = Stream.iterate(0, i -> ++i).limit(chunkTotal)
                .map(i -> ComposeSource.builder().bucket(bucket_video).object(chunkFileFolderPath + i)
                        .build()).collect(Collectors.toList());
        // 源文件名称
        String filename = uploadFileParamsDto.getFilename();
        // 扩展名
        String extension = filename.substring(filename.lastIndexOf("."));
        // 合并后文件的objectName
        String objectName = getFilePathByMd5(fileMd5, extension);

        ComposeObjectArgs testbucket = ComposeObjectArgs.builder()
                .bucket(bucket_video)
                .object(objectName) // 合并后的文件objectname
                .sources(sourceList) // 指定源文件
                .build();
        //1.合并文件
        try {
            minioClient.composeObject(testbucket);
        } catch (Exception e) {
            e.printStackTrace();
            log.error("合并文件出错,bucket:{},objectName:{},错误信息:{}", bucket_video, objectName, e.getMessage());
            return RestResponse.validfail(false, "合并文件异常");
        }
        // 2.校验合并后的和源文件是否一致，视频上传才成功
        File file = downloadFileFromMinIO(bucket_video, objectName);
        // 计算合并后文件的md5
        String mergeFile_md5 = getFileMd5(file);
        if (mergeFile_md5 == null) {
            return RestResponse.validfail(false, "文件校验失败");
        }
        if (!fileMd5.equals(mergeFile_md5)) {
            log.error("校验合并文件md5值不一致,原始文件:{},合并文件:{}", fileMd5, mergeFile_md5);
            return RestResponse.validfail(false, "文件校验失败");
        }
        // 文件大小
        uploadFileParamsDto.setFileSize(file.length());
        // 3.将文件信息入库
        MediaFiles mediaFiles = mediaFileService.addMediaFilesToDb(companyId, fileMd5, uploadFileParamsDto, bucket_video, objectName);
        if (mediaFiles == null) {
            return RestResponse.validfail(false, "文件入库失败");
        }

        // 4.清理分块文件
        clearChunkFiles(chunkFileFolderPath, chunkTotal);

        return RestResponse.success(true);
    }

    /**
     * 清除分块文件
     *
     * @param chunkFileFolderPath 分块文件路径
     * @param chunkTotal          分块文件总数
     */
    private void clearChunkFiles(String chunkFileFolderPath, int chunkTotal) {

        try {
            List<DeleteObject> deleteObjects = Stream.iterate(0, i -> ++i)
                    .limit(chunkTotal)
                    .map(i -> new DeleteObject(chunkFileFolderPath.concat(Integer.toString(i))))
                    .collect(Collectors.toList());

            RemoveObjectsArgs removeObjectsArgs = RemoveObjectsArgs.builder().bucket(bucket_video).objects(deleteObjects).build();
            Iterable<Result<DeleteError>> results = minioClient.removeObjects(removeObjectsArgs);
            results.forEach(r -> {
                DeleteError deleteError = null;
                try {
                    deleteError = r.get();
                } catch (Exception e) {
                    e.printStackTrace();
                    log.error("清楚分块文件失败,objectname:{}", deleteError.objectName(), e);
                }
            });
        } catch (Exception e) {
            e.printStackTrace();
            log.error("清楚分块文件失败,chunkFileFolderPath:{}", chunkFileFolderPath, e);
        }
    }


    /**
     * 从minio下载文件
     *
     * @param bucket     桶
     * @param objectName 对象名称
     * @return 下载后的文件
     */
    public File downloadFileFromMinIO(String bucket, String objectName) {
        //临时文件
        File minioFile = null;
        FileOutputStream outputStream = null;
        try {
            InputStream stream = minioClient.getObject(GetObjectArgs.builder()
                    .bucket(bucket)
                    .object(objectName)
                    .build());
            //创建临时文件
            minioFile = File.createTempFile("minio", ".merge");
            outputStream = new FileOutputStream(minioFile);
            IOUtils.copy(stream, outputStream);
            return minioFile;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return null;
    }


    //得到分块文件的目录
    private String getChunkFileFolderPath(String fileMd5) {
        // 分块存储路径：md5前两位为两个目录，chunk存储分块文件
        return fileMd5.charAt(0) + "/" + fileMd5.charAt(1) + "/" + fileMd5 + "/chunk/";
    }

    /**
     * 得到合并后的文件的地址
     *
     * @param fileMd5 文件id即md5值
     * @param fileExt 文件扩展名
     * @return
     */
    private String getFilePathByMd5(String fileMd5, String fileExt) {
        return fileMd5.charAt(0) + "/" + fileMd5.charAt(1) + "/" + fileMd5 + "/" + fileMd5 + fileExt;
    }


    //获取文件的md5
    private String getFileMd5(File file) {
        try (FileInputStream fileInputStream = new FileInputStream(file)) {
            String fileMd5 = DigestUtils.md5Hex(fileInputStream);
            return fileMd5;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }


    //获取文件默认存储目录路径 年/月/日
    private String getDefaultFolderPath() {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        String folder = sdf.format(new Date()).replace("-", "/") + "/";
        return folder;
    }


    // 根据扩展名获取mimeType
    private String getMimeType(String extension) {
        if (extension == null) {
            extension = "";
        }
        // 根据扩展名取出mimeType
        ContentInfo extensionMatch = ContentInfoUtil.findExtensionMatch(extension);
        //通用mimeType，字节流
        String mimeType = MediaType.APPLICATION_OCTET_STREAM_VALUE;
        if (extensionMatch != null) {
            mimeType = extensionMatch.getMimeType();
        }
        return mimeType;
    }

    /**
     * @param localFilePath 文件地址
     * @param mimeType      文件类型
     * @param bucket        桶
     * @param objectName    对象名称
     * @return void
     * @description 将文件写入minIO
     */
    public boolean addMediaFilesToMinIO(String localFilePath, String mimeType, String bucket, String objectName) {
        try {
            UploadObjectArgs uploadObjectArgs = UploadObjectArgs.builder()
                    .bucket(bucket) // 桶
                    .filename(localFilePath) // 指定本地文件路径
                    .object(objectName) // 对象名 放在子目录下
                    .contentType(mimeType) // 设置媒体文件类型
                    .build();
            // 上传文件
            minioClient.uploadObject(uploadObjectArgs);
            log.info("上传文件到minio成功,bucket:{},objectName:{}", bucket, objectName);
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            log.error("上传文件到minio出错,bucket:{},objectName:{},错误原因:{}", bucket, objectName, e.getMessage(), e);
            XueChengPlusException.cast("上传文件到文件系统失败");
        }
        return false;
    }

}
